1. Field of the Invention
This invention relates to repeating animal traps, and relates more particularly to an escape-proof animal trap of the inclined plane type adapted to catch and confine a number of targeted animals while automatically resetting itself.
Although the concepts of the instant invention are equally applicable to traps for animals of any size, devices of this type are primarily utilized in connection with the trapping of rodents such as mice and rats and, therefore, further discussion herein will be primarily directed to this application.
2. Description of the Prior Art
Repeating animal traps are well known. The commercial embodiments of such traps currently available comprise a housing defining an enlarged enclosure with one, or perhaps two, inclined plane trap assemblies communicating the interior of the enclosure with the exterior of the housing via an elongated passageway. An inclined plane tilting floor member is positioned in the passageway of each trap assembly and is adapted to lift a door to block an entrance opening when the rodent passes beyond a pivot point thereby limiting escape from the enclosure. When the rodent exits the passageway into the enclosure, the door falls by gravity on the entrance end of the tilting floor to reset the trap and the raised end of the tilting floor limits the ability of a captured rodent to return to the passageway.
Captured rodents will attempt to escape in any way possible. Rodents in the enclosure will try to grasp the inner end of the tilting floor to regain access to the passageway. In some instances, rodents on the tilting floor have been able to grasp the side or top edges of the door with their claws or teeth to pull the door down against their own weight, and thereby escape from the trap.
Attempts have been made to limit access to the tilting floor and the door by incorporation of various flanges or lips on the trap assembly walls or roof, but such efforts have had limited success. Since the principal purpose of a repeating animal trip is to capture and retain the targeted animals for subsequent disposition by an exterminator or the like, the effectiveness of a trap that permits escape of a captured animal is greatly diminished and a construction that is, for all intents and purposes, escape-proof, would have significant commercial appeal.
Another problem associated with repeating animal traps is the tendency of a captured rodent to crawl under, or nest in, the space between the bottom wall of the trap housing and the undersurface of the raised end of the tilting floor when the trap assembly has been reset. The presence of an animal in this location prevents another rodent attempting to enter the trap assembly from tilting the floor and, thereby, being captured. Further, a dead animal in this space effectively destroys the use of the repeating animal trap without extensive maintenance. Provision of means to preclude an animal from entering or nesting in this space would be an obviously desirable feature of a repeating animal trap.
It is a well known tendency of mice and rats to stay close to walls in a room, rather than running into the open. If a repeating rodent trap is set against a wall with either or or both of the entrance openings juxtaposed to the wall, the aroma of bait in the housing will generally attract the animal into the trap. However, some rodents will pass by the entrance opening and, thereby, avoid being caught. To some extent, this problem has been minimized by the provision of confining members such as slidable plates secured to the side portion of the housing spaced from the wall to direct rodents that bypass the trap entrance back in the direction of the trap. Yet, some mice or rats will tend to literally climb over the housing to get from one side of the trap to the other without entering the trap. Incorporation of a supplemental trap means to capture a rodent passing over the housing would obviously enhance the effectiveness of the trap.
Since repeating animal traps are generally intended for multiple uses, they have been commonly made of sheet metal, such as aluminum sheet or the like, for durability. While some traps made of plastic have been marketed, the ability to produce a repeating animal trap which is virtually escape-proof, with the major components being formed of plastic, would significantly reduce manufacturing costs and enhance versatility.